Generally known DAF systems include a tank into which influent flows for the separation of solid contaminants. One or more discharge devices are distributed about the tank to discharge a dissolved air or gas and water mix into the influent. As the dissolved gas comes out of the gas/water mix or solution, bubbles are formed. Solids in the influent adhere to the bubbles and are carried to the surface of the influent as the bubbles rise thereby separating the solids from the influent to provide the separated clarified water. In known DAF systems, the gas/water solution is discharged from the discharged devices either in the direction of flow or otherwise in a uniform manner through the tank.
Moreover, known systems use a single dissolved air/gas generation source. In order to provide the dissolved gas/water solution, DAF system require a compressed gas source and a water source. The gas and water are mixed under pressure to dissolve the gas in the water. In known DAF systems using multiple devices to discharge the gas/water solution into the influent, each discharge device is connected to the common or single or dissolved air/gas source. One problem with piping from a single source is that there can be a pressure drop or head loss in the transmission or piping lines which can cause variability in the bubbles size when the gas comes out of solution.
The water used to generate the gas/air solution mix can present a limitation to certain applications of the DAF. More specifically, the water in the gas/water solution generation must be of sufficient clarity so as not to damage or plug the gas/water solution equipment, piping or discharge devices. This can present a limitation in using DAF systems at a site, for example at some remote oil drilling sites, in which fresh or sufficiently clarified water is scarce. Alternatively or additionally, providing sufficiently clear water can increase operating cost of the DAF systems.